Vapor-rectifier.



Q. A. BRACKETT.

VAPOR RECTIFIER.

APPLICATION FILED MAYM. 191s.

1,289,099. Patented Dec. 31,1918.

ll Ill. llllll ll WITNESSES: l INVENTOR @X flug'gq A Brae/r677 UNITED STATES PATENT OFFICE.

QUINCY A. BRACKETT, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF IPENNSYLVANIA.

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Patented Dec. 31, 1918.

Application filed May 1;, 1915. Serial No. 28.073.

To all whom it may concern:

Be it known that I, QUINCY A. BRACKE'I'I, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Vapor-Rectifiers, of which the following is a specification.

My invention relates to vapor electric devices and it has for its object to promote the flow of current therein at the proper times and places and to effectively prevent current fiow under other conditions.

In the accompanying drawing, Figure 1 is a side view of a vapor rectifier of the glass type constructed inaccordance with my invention; and Fig. 2 is a diagram showing the effect of certain auxiliary apparatus upon the potential gradient within the rectifier.

In the operation of vapor rectifiers, it is well known that there is a tendency to establish short circuits directly between the anodes in a double anode device and to establish reverse current flow in a rectifying system embodying two rectifiers of the single anode type.

By my invention, I restrict or entireliy do away with harmful arcing and accor ingly I am enabled to operate rectifiers at higher voltages and at higher current densities thanwould otherwise be possible or I may cause a rectifier to operate satisfactorily on a given voltage wherewith it would otherwise be unstable. I secure these desirable results by mounting an auxiliary electrode, preferably in the form of wire auze, adjacent to each anode and connect- 111 said electrodes to a point in the supply circuit so that the potentials thereof vary in synchronism with those of the anodes. By this connection, the auxiliary electrodes affect the potential gradient within the device and control the flow of current therethrough in somewhat the same manner as the current flow in the local circuit of the well known audion wireless detector is controlled by the high voltage impulses received from the antenna.

Referring to Fig. 1 for a more detailed understanding of my invention, a container the container 3, as is customary 3, composed preferablyof glass, is provided with a pair of main anodes 4: and 5, a main cathode 6 of reconstructing material, such, for example, as mercury, and with an auxiliary anode 7. The anodes l and 5 are placed near the extremities of outwardly and upwardly extending. arms 8 and 9 on in the art. Terminals 1n any suitable source of singlephase alternating current, such, for exam-' ple, as the secondary winding 10 of a transformer 11, are connected to the anodes 4 and 5 and the mid point of said secondary winding is connected to the cathode 6 through any suitable load, such, for example, as a storage battery 12 as is customary.

The rectifier is so designed that the main 7 I electrodes thereof are widely separated so that operation in the ordinary manner withthe voltage of the secondary winding 10 would be rather unstable, because of the inability of theincoming positive wave to properly establish its path. I thereupon provide each of the arms 8 and 9 with a screen-like partition 13, preferably composed of iron wire. Sui-table connections are madefrom the screens 13 to points in the secondary winding 10, preferably through resistance members 1414 or, if desired, through condensers.

Having thus described the structure of my invention, the operation is as follows: Neglecting the inherent differences in the. potential gradient of the normal vapor arc, the potential gradient between, for example, the anode 5 and the cathode 6, may be represented by a straight line'1516 in Fig. 2. The steepness of tiis potential gradient at the voltage of the secondary winding 10 is not sufficient to establish a discharge within the rectifier, under ordinary circumstances. If now, for example, the leads of the screens 13 are connected directly to the associated anode leads, the potential gradient within the device may be represented by the broken line 15-17--16, the horizontal portion 1-5.-17 representing the space between the anode and its associated screen across which the potential gradient has a steepness of zero value and the portion 17-16 represents the potential gradient from the screen 13 to the cathode 6, having such a steepness as to result in breaking down the normal resistance of the arc path 12 and allowing the initiation of current fiow. When, however, the leads of the screens 13 are connected to points outside of the taps of the main angdes 4 and 5 on the secondary winding 10, as illustrated 1n Fig. 1, av higher potential will be impressed upon the screen 1313 than upon the ad]acent anode and the @potential gradient wlthin the device may be represented by a broken line 1518--16 in Fig. 2. When a positive wave comes to a main anode,as, for example, 5, the associated screen 13 M11, at the same instant, be charged to a still higher positive potential and the ascending line 1618 will represent the ascending potential gradient from the main anode to its associated screen. In like manner, the descending portion 1816- will represent the potential gradient from the screen to the main cathode 6. By this connection it Wlll be seen that positive means are provided for causing the rectifier 13 to operate on the potential of the winding 10 without any great tendency to short circuit between the main anodes 4 and 5.

My invention has the further advantage that, when a negative wave comes to a main anode, the associated screen will be, at the same instant, charged to a still higher negative potential and any tendency for short circuiting from the other mainanode will take place to the screen and not to the temporarily negative main anode. ,As the screens 13 are connected to the source through resistance members 14 of high value, any such tendency to short circuit will be reduced to a minimum on account of the small amount of current flow that other. Assume a group of electrons or negatively charged ions to leave the anode 4 and to travel toward the anode 5, as would happen when the anode 4 is negative with respect to the anode 5. The right hand screen 13 is at this instant negatively charged to a higher value than is the anode 4. .Sa id screen, therefore, exerts a repulsion effect upon said electrons, forcing them back upon; the anodes 4 and preventing their travel to the anode 5, Thus, the initiation and maintenance of a short-circuited are between the cathodes is largely prevented.

The short circuit are between the- While I have shown invention in its preferred form, it will be obvious to those skilled in the art that it is susceptible of various minor changes and modifications without departing from the spiritthereof and I desire, therefore, that no limitations shall be placed thereupon except such as are imposed by the prior art or are specifically set forth in the appended claims.

I claim as my invention: 1. Ina vapor electric device, the combination with a container provided with a laterally extending arm, of an anode located adjacent the end of said arm, a cathode within said container, a supply circuit for establishing current flow between said anode and said cathode, a conducting screen extending across the interior of said arm between said anode and the container, and a connection from said screen to a point in said circuit which oscillates in polarity in synchronism with the associated anode and is at all times of greater potential than said anode.

2. In a vacuum-type electric device, the

combination with a'cathode, of an anode, a

conducting member therebetween, and connections whereby, when said anode 1s negative 1n polarity, sa1d conducting member 'is negatively charged to a greater degree.

3. In a vacuum type electric apparatus,

.the combination with a cathode, of two anodes between which a tendency to shortcircuit exists, and a conducting member mounted adjacent to one of said anodes and arranged to be negatively charged to a higher degree than the adjacent anode when sa1d anode is negatively charged.

4. The combination with a source of alternating current, of a vacuum-type electric device embodying two anodes and a cathode, connections from said anodes to spaced points in said source, a connection from said cathode to an intermediate point in said source, conducting members mounted in the arc path between each anode and said cathode, respectively, and connections from.

each of said conducting members to a point in said source outside the point of attachment of the associated anode, respectively.

5.. The combination with a source of alternating current, of a vacuum-type electric devlce embodying two anodes and a cathode,

connections from said anodes to spaced bers to a point in said source outside the points in said source, a connection from point of attachment of the associated anode, said cathode to an intermediate point in respectively.

said source, conducting screen members dis- In testimony whereof, I have hereunto posed across the arc path between each anode subscribed my name this 29th day of April and said cathode, respectively, and connec- 1915. tions from each of said conducting mem- QUINCY A. BRACKETT. 

